linux-kernel - [PATCH v5 43/68] non-consuming variant of do

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Message-ID: <20260114043310.3885463-44-viro@zeniv.linux.org.uk>
Date: Wed, 14 Jan 2026 04:32:45 +0000
From: Al Viro <viro@...iv.linux.org.uk>
To: linux-fsdevel@...r.kernel.org
Cc: Linus Torvalds <torvalds@...ux-foundation.org>,
	Christian Brauner <brauner@...nel.org>,
	Jan Kara <jack@...e.cz>,
	Mateusz Guzik <mjguzik@...il.com>,
	Paul Moore <paul@...l-moore.com>,
	Jens Axboe <axboe@...nel.dk>,
	audit@...r.kernel.org,
	io-uring@...r.kernel.org,
	linux-kernel@...r.kernel.org
Subject: [PATCH v5 43/68] non-consuming variant of do_mknodat()

similar to previous commit; replacement is filename_mknodat()

Signed-off-by: Al Viro <viro@...iv.linux.org.uk>
---
 Documentation/filesystems/porting.rst |  6 +++---
 fs/init.c                             |  3 ++-
 fs/internal.h                         |  2 +-
 fs/namei.c                            | 17 ++++++++---------
 4 files changed, 14 insertions(+), 14 deletions(-)

diff --git a/Documentation/filesystems/porting.rst b/Documentation/filesystems/porting.rst
index ace0607fe39c..7e68a148dd1e 100644
--- a/Documentation/filesystems/porting.rst
+++ b/Documentation/filesystems/porting.rst
@@ -1339,6 +1339,6 @@ in-tree filesystems have done).
 
 **mandatory**
 
-do_{mkdir,link,symlink,renameat2}() are gone; filename_...() counterparts
-replace those.  The difference is that the former used to consume
-filename references; the latter do not.
+do_{mkdir,mknod,link,symlink,renameat2}() are gone; filename_...()
+counterparts replace those.  The difference is that the former used
+to consume filename references; the latter do not.
diff --git a/fs/init.c b/fs/init.c
index 9a550ba4802f..543444c1d79e 100644
--- a/fs/init.c
+++ b/fs/init.c
@@ -140,7 +140,8 @@ int __init init_stat(const char *filename, struct kstat *stat, int flags)
 
 int __init init_mknod(const char *filename, umode_t mode, unsigned int dev)
 {
-	return do_mknodat(AT_FDCWD, getname_kernel(filename), mode, dev);
+	CLASS(filename_kernel, name)(filename);
+	return filename_mknodat(AT_FDCWD, name, mode, dev);
 }
 
 int __init init_link(const char *oldname, const char *newname)
diff --git a/fs/internal.h b/fs/internal.h
index 03638008d84a..02b5dec13ff3 100644
--- a/fs/internal.h
+++ b/fs/internal.h
@@ -60,7 +60,7 @@ int may_linkat(struct mnt_idmap *idmap, const struct path *link);
 int filename_renameat2(int olddfd, struct filename *oldname, int newdfd,
 		 struct filename *newname, unsigned int flags);
 int filename_mkdirat(int dfd, struct filename *name, umode_t mode);
-int do_mknodat(int dfd, struct filename *name, umode_t mode, unsigned int dev);
+int filename_mknodat(int dfd, struct filename *name, umode_t mode, unsigned int dev);
 int filename_symlinkat(struct filename *from, int newdfd, struct filename *to);
 int filename_linkat(int olddfd, struct filename *old, int newdfd,
 			struct filename *new, int flags);
diff --git a/fs/namei.c b/fs/namei.c
index 21a2dbd8b9e6..ca524c5b18f4 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -5072,8 +5072,8 @@ static int may_mknod(umode_t mode)
 	}
 }
 
-int do_mknodat(int dfd, struct filename *name, umode_t mode,
-		unsigned int dev)
+int filename_mknodat(int dfd, struct filename *name, umode_t mode,
+		     unsigned int dev)
 {
 	struct delegated_inode di = { };
 	struct mnt_idmap *idmap;
@@ -5084,12 +5084,11 @@ int do_mknodat(int dfd, struct filename *name, umode_t mode,
 
 	error = may_mknod(mode);
 	if (error)
-		goto out1;
+		return error;
 retry:
 	dentry = filename_create(dfd, name, &path, lookup_flags);
-	error = PTR_ERR(dentry);
 	if (IS_ERR(dentry))
-		goto out1;
+		return PTR_ERR(dentry);
 
 	error = security_path_mknod(&path, dentry,
 			mode_strip_umask(path.dentry->d_inode, mode), dev);
@@ -5123,20 +5122,20 @@ int do_mknodat(int dfd, struct filename *name, umode_t mode,
 		lookup_flags |= LOOKUP_REVAL;
 		goto retry;
 	}
-out1:
-	putname(name);
 	return error;
 }
 
 SYSCALL_DEFINE4(mknodat, int, dfd, const char __user *, filename, umode_t, mode,
 		unsigned int, dev)
 {
-	return do_mknodat(dfd, getname(filename), mode, dev);
+	CLASS(filename, name)(filename);
+	return filename_mknodat(dfd, name, mode, dev);
 }
 
 SYSCALL_DEFINE3(mknod, const char __user *, filename, umode_t, mode, unsigned, dev)
 {
-	return do_mknodat(AT_FDCWD, getname(filename), mode, dev);
+	CLASS(filename, name)(filename);
+	return filename_mknodat(AT_FDCWD, name, mode, dev);
 }
 
 /**
-- 
2.47.3